Process of making composite metals.



completely filled mixture, the attem UNITED STATES PATENT OFFICE.

I THOMAS A. EDISON, OF LLEWELLYN PARK, .N EW JERSEY.

PROCESS OF MAKING COMPOSITE METALS- To all whom, it may concern:

Be it known that I, THOMAS ALVA EnisoN,

a citizen of the United States, residing at als, of which the followingls'a description.

My invention relates to the formation of a new product-namely, acomposite metal, in which two or more metals are hysically admixed insuch a way that eacfi metal exists as a practically integral sponge-likestructure, the cells or ores of elther metal being the body presented bythe other metal, w ereby the entire bulk of the composite structure as aWhole will be continuously solid throughout. Such a composite metal ischaracteristically distinuished from any so-called alloy heretoforemade, so far as I know, in the res ect that it consists of sponge-likeinterloc g masses, so that it becomes possible by dissolving orotherwise removing one of the metals to obtain a sponge-like integralmass of the other metal, whereas with ordinar alloys, owing to theirintimate molecular a t to dissolve any one of the constituents o thealloy results in the disintegration of the mass. This characteristicpeculiarity of m improved composite metal makes it possib e to securevery beau tiful sponge-like effects in various metals by firstformlngthe composite metal and then removing one of the metals, and it alsobecomes possible to secure attractive efiects in many arts where it isdesirable that two or more metals should be mechanically associatedtogether. The primary purpose for which I have used the composite metalreferred to is for the production of scales, flakes, or foils of nickeland cobalt for admixture vwith the active material in the negativeelectrode of my improved storage battery. As I have pointed out inapplication for Letters Patent filed concurrently herewith, Serial No.252,935, good contact with such, active material and between the flakesor foils themselves is secured when metallic cobalt is used; but as Ihave explained it is undesirable to use metallic cobalt alone, owin tothe fact that its surface becomes oxidize by electrolysis and might intime penetrate the whole mass, and hence it might be advisable to makeuse of a composite metal of cobalt and nickel. Such a composite metalserves Specification of Letters Patent. Application filed MarchSO, 1905.Serial Ne- 252,933.

- Patented Aug. 7, 1906.

to "ivc "excellent contact, and the presence of file nickel thereinprevents penetration of oxid within the nickel-cobalt to a harmfulextent, since the metallic nickel fori'ns a continuous integralconnecting -'sponge, and therefore protects the cobalt from thepossibility of inward oxidation to any harmful extent.

Assuming a composite metal of nickel and cobalt to be manufactured forthe purpose of forming scales, films, or foils for usin the make-up ofmy improved battery, I proceed substantially as follows: A solution ofsulfate of nickel and sulfate of cobalt is first obtained inthc properrelative quantity to give to the resulting product the desiredproportions of the two metals: Excellent results have been secured witha composite metal containing sixty per cent-of cobalt and forty percent. ofnickel but these proportions may e varied within quite widelimits. The solution of cobalt and nickel sulfates is now added to apotash solution in excess of that necessary to precipitate the twosalts, andthe two solutions thus added are boiled, resulting in theprecipitation of hydroxids of nickel and cobalt, which are allowed tosettle. The

solution is now drawn off and the precipitated mixed hydroxids arewashed successively until the mass is free of potash and sulfates. Inthis way I obtain a physically and intimately mixed mass of hydroxidsof'the two metals in the desired pro' ortion. The mixed hydroxids arenowdrie and screened into granules of substantially uniform size forinstance, those passing a thirty-mesh screen and arrested by asixty-mesh screenafter which the iranules are subjected to the reducingaction 13; hydrogen-gas in a heated retort to reduce t e hydroxids tothe respective metals and also to weld together the metallic particlesconstituting each of the granules, so that each granule willbe com posedof a combination of the two metals having the characteristics beforepointed out. The reduced metallic granules are now sub- 'ected tosuccessive rolling operations with oil to convert the composite metalinto fine scales or flakes, as is common in the art, for example, ofmaking bronze-powder. Preferably the flakes are annealed two or moretimes between the passes of the rolling operation in an inert as, suchas hydrogen, at a red heat. After t e flakes or foils are formed to passthem between very fine crimpingrolls, by which they Wlll be crunped,corrugated, or otherwise distorted, or between rolls of ve smalldiameter, by which they will be curled or formed into minute spirals.These flakes or foils are added to the active material of the battery inany suitable way-for example, as I have described-in my concurrentapplications, Serial Nos. 252,929 and 252,930, 'wherein theconductin-flakes are first assembled and then welde to'constitute a sponge-likeor hone comb structure, in which the active materia is introduced bysuccessively dipping the same into a saturated solution of the activesalt and alternate evaporation of the solvent; or'instead the activeparticles may be coated with a sticl? material, such as molasses, andthen a 7 mixed with the metallic flakes or scales, be-

ing then assembled in the pockets, a moderate pressure applied, themolasses being then dissolved out and the final pressure applied, as Idescribe in my concurrent application, Serial No. 252,931.

Having now described my invention, what I claim as new therein, anddesire to secure by Letters Patent, is as follows:

1. The process of manufacturing compose its metals which consists infirst forming an intimate admixtln'e of reducible salts of two or moremetals and finally in subjecting the mixture to the effect of heat in areducing atmosphere to reduce the same to the metallic state and weldthe particles together, substantially as set forth.

2. The process of manufacturing compos- -ite metals, which consists infirst making a solution of soluble salts of two or more metals, then inprecipitating reducible-salts of the two metals from such solution,Whereby an intimate physical mixture will be secured, and finally insubjecting the reducible salts to the effect of heat in-a reducinatmosphere-to reduce the salts to the meta ic state and to weld themetallic particles together, 5

substantially as set forth. I

3. The process of a nickel-cobalt composite which consists in firstobtaining a solution of sulfate of nickel and sulfate of cobalt in thedesired proportion, then in preci pitating by means of an alkali, hyoxide 0 the two metals in intimate physical admixture, and in finallysubjectmg said hydroxids to heat in a reducing atmosphere to reduce thehydroxids to the metallic state and to weld the metallic particlestogether, substantially as set fort I 4. The process of making anickel-cobalt composite, which consists in first obta" a' solutionofsulfate of nickel and sulfate of co-- balt in the desired proportion,then in preci itating by means of an alkali hydroxids of nickel andcobalt from said solut1on, then in washing the preci itated hydroxids,and finally in subjecting t e same to the efiectof heat in a reducingatmosphere to reduce the hydroxids to the metallic state and to weld themetallic particles together, substantially as set forth.

5. The process of making a nickel-cobalt composite, which consists infirst obta' a solution of sulfate of nickel and sulfate of cobalt in thedesired proportion, then in preci itating by means of an alkali,hydroxids o the two metals from said solution, then in washing theprecipitated hydroxids, then in drying and screening the same intogranules and finally in subjecting the said granules to the effect ofheat in a re ucing atmosphere to reduce the hydroxids to a metallicstate and to weld the particles together, as and for the pugposes setforth.

his specification signed and wltnessed this 29th day of March, 1905.

THOMAS A. EDISON.

Witnesses: Y

FRANK L.. DYER,

ANNA KLEHM.

